The application of "permanent wave" solutions to achieve hair curl is a process that enjoys great popularity among women and today, even among men. The process has become easier since after World War II with the advent of the home permanent kits.
One of the problems associated with permanent waves, is the fact that the curling aids which are held under pressure tend to come loose. Thus the necessity has arisen for the placement of a cap upon the head to hold the curling rods in proper disposition. Problems arise however when it becomes necessary to rinse and neutralize, as upon removal of the bonnet or cap, the curling rods can come loose.